the McMillan Commission proposed building a dam across the Anacostia River at Massachusetts Avenue SE or at Benning Bridge to form a large lake for fishing and recreational boating. The Commission also proposed using dredged material to build islands within the lake. The Washington Post reported in July 1914 that Congress had approved the plan for a dam on the river at Massachusetts Avenue SE. By 1916, the Corps of Engineers was still planning a dam, with access to the deep lake behind it controlled by locks. The Corps also planned to create several large islands in the lake and planned to replace Benning Bridge with a drawbridge to accommodate cargo ship traffic through the lake. The firm of Sanford and Brooks began the dredging in January 1903, at which time the Army Corps of Engineers began surveying the surrounding land to determine whether the federal government or private landowners had title to the marshes themselves. The survey work was complete by November 1905, with the U.S. government asserting ownership over the flats. In June 1912, Congress appropriated $100,000 to dredge the Anacostia from the 11th Street Bridges to the District-Maryland line. In June 1915, the dredges discovered two large anchors with many feet of chain attached to them. The anchors were believed to have come from United States Navy gunboat barges burned on the Anacostia River in 1814 during the War of 1812. Both Kingman Island and Heritage Island were completed in 1916. Ownership and plan changes In 1915, ownership of the newly created land became an issue in a lawsuit. The boundary of the District of Columbia had been set by the Black-Jenkins Award, a decision by an arbitration panel in 1874 which resolved centuries of dispute by placing Virginia's boundary with Maryland at the low-water mark on the Virginia side of the Potomac River. The Virginia retrocession of 1846-1847 returned a portion of the District of Columbia on the Virginia site of the Potomac River to the state of Virginia. This left in doubt the exact position of the District's border with Virginia. In Morris v. United States, 174 U.S. 196 (1899), the Supreme Court of the United States held that land built in the Potomac River not only belonged to the District of Columbia but to the federal government (contrary to the claims of private landowners, who believed the property belonged to them). In Maryland v.